Accomplishment Of π/4QPSK And Its Performance Analysis In The Rayleigh Fading Channel

π/4QPSK is a quadrature phase shift keying modulation, and it has the virtue of QPSK and OQPSK. The performance of π/4QPSK is better than OQPSK under the condition of multipath spread and fading, In North America and Japan π/4QPSK has been adopted by the digital cellular communication systems. This paper introduces the modulation of BPSK,QPSK, π/4QPSK and the classification of fading channels; and simulates the transmission and reception of π/4QPSK signal. At last, the performance of π/4QPSK in the Rayleigh fading channel is analysed.Digital modem application-specific integrated circuits make the sending and receiving devices more compact in the communication transmission, reduce costs and power consumption, and improve the reliability of the equipment. Meanwhile, the adaptation of digital modulation technique makes all kinds of modern modulation techniques as one, and makes the modem applicable to all kinds of modulation and the rate variable, In North America and Japan,π/4QPSK has been adopted in digital cellular mobile communication system.